Investigations on the cuticle of the polychaete elytra using energy dispersive X-ray analysis

Abstract

Energy dispersive X-ray analysis of elements with Z>11 in a SEM (scanning electron microscope) was used to investigate the elytra of Lagisca extenuata, Lepidonotus clava, and Harmothoe areolata from Naples (Italy) and Banyuls (France). High concentrations of halogens and a few other elements were found in certain papillae in samples from both locations. Additional TEM-examinations and X-ray analysis of thin sections revealed that the halogen concentration is inversely related to the collagen content of the matrix. The halogens are presumably bound to tyrosines, which occur in these structures. In addition, accumulation of Mn2+ and possibly Fe3+ in the papillae might depend on environmental conditions. The results show that valuable information about the chemical composition of biological structures can be obtained by energy dispersive X-ray analysis. Moreover, the results indicate that this method may be useful for environmental investigations. © 1981 Biologische Anstalt Helgoland.